How to Make It
Peel the watermelon. This may seem daunting, but a Y-shaped peeler does the trick pretty handily. Once it's been denuded, quarter the melon with a sharp knife, then on each side, run the blade along the place where the pink flesh meets the white rind, slicing in as far as you can go. Then, starting at one tip, slide the blade in and separate the flesh from the rind. Use a spoon to scrape off as much pink as you can, and reserve all the watermelon flesh for whatever you'd normally do with that.
Slice the rind into strips of a size that pleases you, removing stem ends. Place the strips in the Instant Pot (or the pressure cooker of your choice) along with lemon slices. Sprinkle with salt, sugar, and hot sauce. Cook at high pressure for 10 minutes, then manually release the pressure.
Pour into a lidded container and cool. Eat the watermelon and lemon as a snack or condiment, and shake the flavorful brine over ice with your favorite spirit for a bonus cocktail. They'll keep in the refrigerator for about a week.